Sofa



FIG. 1 is a front perspective view of a sofa, showing my new design;

FIG. 2 is a right side view thereof, the opposite side being a mirror image thereof;

FIG. 3 is front view thereof; and,

FIG. 4 is a front and top view thereof. 

CLAIM I claim, the ornamental design for a sofa, as shown and described. 